Reinforcing yarns of polyester, nylon and steel have been used in tires. While these materials have been overall successful in the past, recent demands in the tire industry have pushed the expected performance into new levels. To meet this demand, it has been contemplated to use multi-filament reinforcing carbon yarn to reinforce the tire. Unfortunately, the degree of adhesion between the yarn and its rubber environment have not been satisfactory. Therefore, any improvement in the adhesion between a carbon yarn and its rubber environment will permit those in the tire industry to meet the expected performance requirements.